Iodine NQR and Phase Transitions in [N(CH3)4]2ZnI4*
نویسندگان
چکیده
Using a superregenerative NQR spectrometer, the temperature dependence of I NQR spectra in [N(CH3)4]2ZnI4 was measured between 167 and 335 K. The measurements confirm two known structural phase transitions at 219 and 257.5 K. The correspondence between the distinct regions of iodine NQR spectra and the crystal structure is discussed. The relation of [N(CH3)4]2ZnI4 to the incommensurate family with the general formula X2YZ4 and the high temperature (paraphase) crystal space group D ^ (Pmcn) is studied.
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